1. Field of the Invention
The invention pertains to an illuminating device with optical conductors for escalators or moving walkways, which includes a movable stair or pallet belt and having at least one vertical balustrade arranged laterally thereof as well as a hand rail guided at the upper end thereof in a further rail, wherein light, from at least one central light source, is guided to individual illumination points along the escalator or the moving walkway, by optical conductors extending at least partially along the balustrade. Such illumination or lighting generally serves in escalators or moving walkways to increase user safety and to improve the decorative display via special light effects.
2. Discussion of the Background of the Invention and Material Information
Generally, the illuminators or lights for escalators and moving walkways are constructed in the form of elongate fluorescent lamps which are arranged below the hand rail or recessed balustrades, whereby also a degree of protection against vandalism is assured by the recessed arrangement. Such conventional illumination equipment is however not well suited for installation in escalators and moving walkways with so-called narrow profile balustrades, which because of their small volume profile, below the hand rail, look very elegant and for that reason enjoy increasing popularity. The installation of elongate large volume fluorescent lamps into the narrow balustrade profiles would result in constructional and aesthetic problems.
On the other hand, illumination devices however have become known, which also enable adequate illumination for narrow profile balustrades without impairing the optical overall impression of the particularly delicate balustrade profile or reducing its decorative effect. Such solutions consist essentially of lamps of small dimensions that are situated below the hand rail or in the balustrade pedestal. Hitherto, smaller low-voltage tubes or Halogen lamps were generally used for this purpose.
Both low-voltage tubes and Halogen lamps suffer from the disadvantage that a relatively large number of lamp units must be used, which, because of their differing service lives, leads to frequent additional service operations at the escalators or moving walkways. Halogen lamps moreover present heat problems, and require very efficient insulation, because of their relatively high heat radiation, so that no hot installation parts result, which the users of the escalators or moving walkways can come into contact therewith. Moreover, low-voltage tubes such as Halogen lamps must be so installed that they can be exchanged in a problem-free manner. The escalator step region, which is important from the safety standpoint relative to stepping thereon, also often remains only inadequately illuminated so that it becomes necessary to mount additional illumination devices in the region of the comb plate for entry or exit purposes. Later added improvements of this type impair the elegant appearance of the narrow profile balustrades and are often perceived as purely functional illuminations.
Furthermore, an escalator with a balustrade as well as a hand rail guided at the upper edge of same, in which a stationary optical conductor consisting of light-conducting fibers is mounted in a rectangular cavity underneath the hand-rail, is set forth in German Patent Publication DE 42 09 505 C1. The cavity of rectangular cross-section is closed off downwardly by a transparent plexiglass or safety glass cover. The rectangular optical conductor consists of a plurality of individual optical fibers which together conduct the light, produced by a light source and fed in at its end face, in the longitudinal direction through the optical conductor. The individual optical fibers however do not extend exactly in longitudinal direction of the optical conductor, but at an extremely acute angle thereto, so that they also impinge on the downwardly directed light exit surface of the optical conductor at this extremely acute angle.
The rectangular cross-section of the optical conductor thus reduces over the length of the optical conductor in the manner of a wedge, wherein the cross-sectional area remaining each time from a full cross-section is filled out by a counter layer. Counter layers, such as optically conducting fibers, are flexible so that the optical conductor can be laid, parallel to the endlessly circulating hand rail, stationarily in the rectangular cross-section cavity lying thereunder. The light, which is fed in by the light source at the end face, is conducted further in the optically conducting fibers until it impinges at an acute angle on the transparent plexiglass or safety glass cover which covers the optical conductor downwardly and is radiated therefrom, parallel to the balustrade wall surface, continuously into the foot region.
Since the optical conductor employed extends along the hand rail over the full length of the upper balustrade rim, the illumination achievable over the stepping path is preset or predetermined by the light conduction and in principle restricted in respect to the light intensity. It might therefore be difficult with this balustrade illumination to adequately illuminate the stepping path with respect to the elimination of danger or the decorative make-up thereof, in all cases. On the other hand, a structuring of the optical conductor, in the sense of an increase in the light yield, leads to a relatively wide build-up which is not well suited for installation into the narrow profile of narrow profile balustrades. Furthermore, the utilized optical conductor is a fiber-optical element, which by reason of its integration into the hand rail must be individually tailored for each installation. An adaptation to different forms of construction or light conditions is hardly possible so that the application of such an optical conductor is greatly restricted with respect to the flexibility and freedom of choice. Here, the invention provides a remedy.